Selenium electron configuration

Tellurium [13494-80-9] Te, at no. 52, at wt 127.61, is a member of the sixth main group. Group 16 (VIA) of the Periodic Table, located between selenium and polonium. Tellurium is in the fifth row of the Table, between antimony and iodine, and has an outer electron configuration of The four inner... 

Tellurium is the fourth element of the VIA family of the periodic table, which starts with oxygen. Since tellurium exhibits an electronic configuration similar to that of selenium and sulphur, the chemical behaviour of these elements is obviously closely related. This similarity was a hindrance to the greater development of tellurium chemistry. During several decades, research was restricted to an extrapolation of well-established reactions for the preparation and use of organic sulphur compounds to selenium, and mainly from selenium to tellurium. 

Due to its 4s24p4 electron configuration, selenium, like sulfur, forms many divalent compounds with two covalent bonds and two lone pairs, and d hybridization is quite common, to form compounds with Se oxidation states of 4+ and 6+. 

Multiple products with formula Cp 2Mo2S4 arise in the reaction of 2 with sulfur (185). One of these has structure 70. A similarly complex reaction occurs for 3, while the product of reacting 3 with selenium is 71 (186). On the other hand, a pentasulfide (72 ) is formed (187) when 1 is treated with an excess of sulfur. Its structure is interesting the five sulfur atoms adopt a planar configuration. Eighteen-electron configurations are attained in 72 provided a Cr=Cr bond is accepted. 

The cyanate ion has the ground-state electronic configuration lu , 2a, 3o , 4a, 6o, 6u , Itt the thiocyanate and subsequent ions are similar unless account is taken of the core electrons or empty d orbitals of sulfur, selenium, or tellurium which increase the complexity of the ground-state description. The most sophisticated calculations that have been carried out on these ions are those of McLean and Yoshimine 506) on NCO" and NCS . The calculated orbital energies are given in Table... 

Drawing a Conclusion The elements aluminnm, silicon, gallium, germanium, arsenic, selenium are all used in making various types of semiconductor devices. Write electron configurations and electron-dot structures for atoms of each of these elements. What similarities among the elements electron configurations do you notice ... 

Polonium is the most metallic member of group 6A. But it is not a typical metal. It is rare, radioactive, and extremely toxic. Polonium is important historically because it was discovered by Marie and Pierre Curie in 1898 and named for Marie s nabve land, Poland. Selenium and tellurium are metalloids oxygen and sulfur are nonmetals. There are some trends to note in group 6A. With six valence electrons, the elements act mainly as nonmetals. They tend to gain two electrons to form ions with a 2— charge they also can share two electrons to achieve a stable electron configuration. 

Bromine has a greater electron affinity than selenium. Gaining the extra electron changes the Br atom into Br, which has a particularly stable closed-shell electron configuration (the same as that of the noble gas atom krypton [Kr]). No such configuration is created when a Se atom gains an additional electron. 

The only chemically stable ion of rubidium is Rb+. The most stable monatomic ion of bromine is Br. Krypton (Kr) is among the least reactive of all elements. Compare the electron configurations of Rb, Br , and Kr. Then predict the most stable monatomic ions of strontium (Sr) and selenium (Se). 

Write abbreviated electron configurations for atomic oxygen, selenium, and polonium. 

Like oxygen, sulfur and selenium are in group 6A on the periodic table, so they too have six valence electrons, with 3s 3p and 4r electron configurations, respectively. We therefore expect sulfur atoms and selenium atoms to have bonding patterns similar to oxygen s. For example, they all commonly form two bonds and have two lone pairs, as in molecules such as H2O, H2S, and H2Se. 

Polonium is a member of the oxygen group of elements and has the electronic configuration [Xe]4H 5d °6s 6p. In this group, there occurs the transition from the typical nonmetals (oxygen and sulphur) to the metalloids (selenium and tellurium) and the metal (polonium). 

Let s use the periodic table to write the electron configuration of selenium (Se, element 34). We first locate Se in the table and then move backward from it through the table, from element 34 to 33 to 32 and so forth, until we come to the noble gas that precedes Se. In this case, the noble gas is argon, Ar, element 18. Thus, the noble-gas core for Se is [Ar]. Our next step is to write symbols for the outer electrons. We do this by moving across period 4 from K, the element following Ar, to Se ... 

The first two elements in Group 16, oxygen and sulfur, have the electron configurations Hg ns np while the heavier elements, selenium and tellurium, have the electron configurations [Ng](n- All the Group 16 elements form thermally stable compounds... 

Use the Aufbau principle to obtain the ground-state t ARiS electron configuration of selenium. 

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